Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Jun. 30, 2019
Entity Information [Line Items]
Entity Registrant Name	TELOS CORP
Entity Central Index Key	0000320121
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Public Float		$ 0
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Document Annual Report	true
Document Transition Report	false
Entity Address, State or Province	MD
Class A Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding	45,098,460
Class B Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding	4,037,628